Answer:
Option (3)
Explanation:
Option (1).
AB and SE are coplanar.
Incorrect.
AB lies in a plane ABS and SE lies in another plane SEL.
Option (2).
TS and SE intersect at E.
Incorrect.
They intersect at S.
Option (3).
R intersects K at SB.
Correct.
Since line of intersection of planes R and K is SB
Option (4)
AB and BL are perpendicular at B.
Incorrect.
Angle between them is not 90°.